Internal-combustion engine.



W. J. WRIGHT.

INTERNAL ooMBUsTroN ENGINE.

APPLICATION FILED MAR. 1912.

1,073,652. Patented sept. 23, 1913.

www M@ W. J. WRIGHT.

INTERNAL GOMBUSTION ENGINE.

APPLICATION TILED MAR. 5, 1912.

1,073,652. Patented sept.23,1913.

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INTERNAL GQMBUSTION ENGINE. APPLICATION FILED MAR.5,1912.

1,073,652, Patented Sept. 23, 1913.

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INTERNAL COMBUSTION ENGINE. APPLICATION FILED MAR. 5, 1912.

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WILLIAM JAMES WRIGHT, OFFRANKLIN, PENNSYLVANIA, ASSIGNOR TO WRIGHT ENGINE COMPANY, F PITTSBURGH, PENNSYLVANIA, A CORPORATIGN OF :DELA- WARE.

INTERNAL-COMBUSTION ENGINE.

To aZZ wherz't may concern:

Be it known that I, WILLIAM J. WRIGHT, residing at Franklin, in the county of Venango and State of Pennsylvania, have invented certain new and useful Improvements in Internal-Combustion Engines, of which the following is a specification.

My present invention is an improved compound internal combustion engine in which the parts are so arranged and designed that there will be no dead center to the engine as a whole and in which at the instant the ignition or explosion takes place after 'the high pressure pistons have compressed the working agent, one of such high pressure pistons will be moving on its working stroke to enable the full force and el'feet o'l' the ignited charge at the instant oif ignition to perform work in propelling the pistons along their working strokes, Vthus increasing the active power and cliiciency of the engine.

The invention also embodies means whereby the high pressure section of the engine is in the nature ot' a duplex differential unit in which a plurality ot' cylinders and pistons are provided, the pistons being so arranged whereby the one passes its dead center l in advance of the. time when the other passes its dead eenterfso that there will be no resultant dead center in the engine as a whole, and thus the objectionable features ot' this nature in the old types oit' engines are, eliminated.

The invention further includes means tor utilizing the heat energy which is usually wasted or dissipated through the cylinder .walls ot the engine and making such heat energy do work on the engine pistons.

My invention also includes means whereby the low pressure cylinder and its piston cooperate with the other parts in such a manner that during a part of the cycle of opera tion ol the low pressure piston, it acts as a scavenging piston to draw otl' the burned mixture through the various ports of the high pressure cylinders and the intercomniunieating ports between one ot the high pressure cylinders and the low pressure cylinder, and simultaneously draw cold air in through the central air ports ot one of the high pressure cylinders to "draw the hot burned mixture into the low pressure cylin- `der against the head of the low pressure pis- Specication of Letters Patent.

Application filed March 5, 1912.

Serial No. 681,789.

in the high pressure cylinders and in the upper end of the low pressure cylinder.

The invention also includes a construction whereby when the exhaust ports are open they are opened next to the low prcssuie )iston head so that on a succeeding part o its cycle ot movement, the low pressure piston will Ytorce the old mixture through the cxhaust ports without disturbing the cold air at the upper end Iot the low pressure cyl inder.

Means are also provided for relieving any vacuum that may be formed in the cylinders during high speed running of the engine.

Again my invention provides a construction in which there are no intercommunicating valves between the several cylinders, and no exhaust valves to become overheated or worn, thus eliminatingT one ot' the chief ohjections to engines ot the internal combustion type.

ln addition to the foregoing, the invention also resides in those novel details o't" construction, combination and arrangement of parts, all of which will be. lirst fully described, then spccilically pointed out in the apl'iended claims, reference being had to the accompanying drawings, in which Figure 1 is a vertical longitudinal section on the line 1 1 ot Fig. 2. Fig. 2 is a horizontal section on the line Q--- of Fig. l. Fig. l is a vertical longitudinal section on thc line 3--23 ot' Fig. Q. l `ig. l is a vertical cross section on the line ft-Mit ot' Fig. Q. Fig. 5 is a detail horizontal section on the line 5-5 ot Fig. Il. l `ig. t3 is a detail vertical section on the line G-G ot' Fig. 3. Fig. 7 is a detail section on the line T--T ol'l Figfl. Figs. 8 to '1Q inclusive are diagrammatic views illustrating the operation ol the invention.

ln the drawings in which like numerals and letters ot reference designate like parts in all the ligurcs, l is the crank case..` which is ot the closed type, and which is provided with hearings 2 and f-l, 'tor the crank sha'l't 4.

5 and t designate the cranks ol the crank Shaft.` there beingl two cranks employed lor the three cylinders hereinafter referred to.

The crank case l is divided by a horizontal partition T, into an upper chamber and a lower chamber 8, which serves as an oil reservoir, the chambers 8 and 55 being in comiuunieation with one or more stand pipes Sl which project up 'troni the bottom Patented Sept. 23, 1913.

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crank shaft bearings. On the down strokes of the several plstons, the 'air 'orfvapor 1n l`the chambers 55 and 8 is compressed, while on the up strokes the air or vapor in the chamber 55 is rareed, thus lcausing a lesser pressure in chamber 55 than there is present in chamber 8l The air from chamber 8 then rushes through pipes 9 into chamber 15, thereby atomizing theoverflowing oil in the pipes 9 and forcing or drawing it as a spray into the chamber 55.

11 and 12 designate the high pressure cylinders, and 13 designates the low pressure cylinder. The ,cylinders 11, 12 and 13 together'with their water jackets 16 are cast integrally and they have flanges 14 through4 which the bolts 15 pass to secure the cylinders to the crank case 1, with the interior of which the cylinders communicate below their respective pistons. The high pressure cylinder 11 carries the high pressure piston 17 which is connected to the crank 6 through the principal connecting rod 19 and pin 18, while the high pressure cylinder 12 has a piston 23 which is connected to the connecting rod 19 by an auxiliary rod 26 and pins 25 and 27, as best shown in Fig. 4' of the drawings. The cylinders 11 and 12 are in communication through ports 20 with a common compression and ignition chamber 21 into which the spark plug 22 of the usual type projects. j The pistons 17 and I23 are suitably packed in any desired manner and the piston 23 has an annular groove or duct 24 between its ends, which will be hereinafter again referred to. rllhe high"p`ressure cylinder 11 has a fuel intake port 28 with which the back check valve 29 communi- Cates, the port 28 heilig controlled principally by the piston 17. The valve 29 communicates with the outlet valve mechanism .31, of the fuel .charging pump 33, through the medium of Ika duct 30. The pump is mounted on the crank casl in the preferred construction, and the valve mechanism 31 includes a valve 32 that is operated by the pump piston 36 which operates in the pump cylinder. The piston 36 receives its motion from a Cain 39 that is secured at 40 to turn with the crank shaft 'l, the cam 39 transmitting its motion through a connecting rod 38 and pin 37 to the piston 36. The working agent is admitted from the fuel pipe through the hack check valve 35 and port 34 into the pump easing 33 as required. The high pressure cylinder 11 is provided with one or more relief valves 41 which open when the engine is running rap'. idly under a light" load to prevent formation of a vacuum in the cylinders and thereby eliminate any drag on the pistons. The high pressure cylinder 12 is provided with a set of ekhaust ports 42 which are controlled by the piston 23 and coperate with the annular groovel 24 thereof. The cylinders 12 and`13 are alsobrought into communicat-ion at times by intercommunicating ports or ducts 43 and 44, the lowerv ones of the ducts 43, which aline `with the port 42, serving aslexhaust ports, while the upper ports 43 and port 44 serve purely as intercommunicating ports 'between the working chambers of the cylinders 12 and 13.

I 45 is the low pressure piston which is connected with the crank 5 by a connecting rod 47, pin 46, and lcrank connection 48.

` 49 is the oil\ pump which pumps the oil from the chamber 8 into the chamber 55, the pump 49 yhaving its plunger 50 connected at 51 to the piston 36 to be operated thereby, and it also has its outlet or discharge port 52 arranged to deliver into the chamber v55, while' the intake pipe 53 is provided with back check valves 54 and conveys the oil from the chainber 8to the pump' 49 bv which it is discharged into the chamber55 through the outlet port 52, and back check valve 58.

The oiling system employed in my present 9 construction forms no part, per se, ofthe present invention-asv it forms the subject matter of my Patent #1,020,007 issued March'12, 1912.

56 is the fiy wheel .of the engine which maybe ofthe usual construction. The cylinder 11 is provided with a piston controlled air intake port 57 thro-ugh which the scavenging agent is admitted into the cylinder-stat the proper time.

59 designates the intake and outlet pipes for the water jacket 16.

peration: Referring now most particularly to the diagrammatic Figs. 8 to 12 inelusive, it will be perceived that when the parts are positioned as indicated in Fig. 8, the cylinder 13 ahead of the piston 45 will be filled with fresh air undergoing compression. The working chambers of the cylinders 11 and 12 and the compression chamber 21 will contain a compressed new charge which has just'been ignited. lt will be noticed that the piston 17 is just at. its dead center while the piston 23 has passed its dead center, therefore. at the instant of the ignitionof the charge the full 'force and effect of the initial pressure will be exerted on the piston 23 immediately, and as soon as the piston 17 starts on its working stroke, it also will be impelled by the charge. lVhen the parts are positioned as shown in Fig. 8, the piston 36 ot'l the fuel ypump will be drawing in a new supply of fuel through the valve 35 and at this time also the valve 32 and the hack cheek valve 29 will be closed. As the parts arrive at the position shown in Fig. 9, the pistons 17 and 23 are being impelled under the influence of the ignited working charge in the cylinders 11 and 12. This Charge is still at high pressure and at this time the piston 23 begins to uncover the' auxiliary intereommunieating port 44 so that the high pressure Working eharge in the cylinders 11 and 12 may passin part through sueh port 44 into the Cylinder 13 and unite with the compressed air in such cylinder to impel all three of the pistons under the inluenee of the working charge. While the parts are moving from the position shown in Fig. 8 to the position shown in Fig. 9, the valves 29 and 31 will be closed and the valve 35 will remain open. 1t should also be understood that while the parts are moving from the position shown in Fig. 3 to the position shown in Fig. t) the ports 41:3 remain closed and the relief valves al together with the air port 57 are also Closed. New assume that the parts pass 'from the position shown in 9 to the position shown in Fig. 10. lln doing this, all three pistons 17, 23 and 415 are impelled under the influence oi the expanding Charge of working agent, the pressure of which is oit eourse rapidly falling. the pump piston 36 (Fig. 10) will also be moving on its upper stroke to compress the new charge ot working agent in the pump cylinder 33. When the parts have reached the position shown in Fig. 10, the piston 23 has reached the lowermost limit oli' its working stroke, and `is about to begin its compression stroke, while the piston 17 still has a short distance oi." travel on its working stroke. The piston 1T in Fig. 10 is also uncovering the air inlet port 27 when the parts have arrived at the position shown in Fig. 10, whereby the pis ton @l5 on its 'further movement 'trom the position shown in Fig. 10 to the position shown in Fig. 11 draws air in through the port 57 into the cylinders 11 and 12 and into the cylinder 13 to draw ont the old charge from the cylinders 11 and 12 and replace them completely with air while suttieient air is admitted into the eylinder 13 so that after the Cylinder 13 has been exhausted of the old Charge, it will eontain, theoretically, only fresh air. `New as the parts move from the position shown in Fig. 10 to the -full line position shown in Fig. 11, the cylinders 11 and .12 will be soavenged and filled with air and 'lresh air will also be contained in the cylinder 13 above the dot and dash line which is the theoretieal plane oit demarcation between the Atresh air and old or exhaust Charge. Now as the parts move from the full line to the dotted line position sho-wn in` Fig. ll, and as soon as the piston 1i1 has elosed the air port 57, the piston 3G et the Charging pump will open the valve 32 and the compressed charge of new working agent will pass into the cylinders 11 and 12 to displace some ot the air therein through the au\iliaryl port 44, which being of small cross seetional area, dees not permit ot' a very rapid passage of the air between the cylinders 12 and 13. As the piston 23 moves on its compression stroke, from the full line to the dotted line position in Fig. 11, it will uncover the eX- haust ports 42 bringing them in alinelnent with the groove 21 o1 the piston 23, so as to bring the lower ports or duets 13 into communication with the exhaust ports or duets 1.12, whereby the piston 115, will foree the old charge beneath the dotY and dash line in Fig. 13 through the lower ports 13 and grooves 211; and exhaust ports ft2 to atmosphere. In moving 'trom the dotted line position of Fig. 11 to the position shown in Fig, 12, the piston 313 begins its suction stroke, the valves 32 and 3U are elosed, the pistons 17 and 23 will be compressing the new charge in the eylinders l1 and l2 and in the ehamber 21, and the piston L.l5 will begin to compress air in the cylinder 13, while the exhaust, port 4t2 will be nearly fully closed by the piston 23. Now when the parts move trom the position shown in Fig. 12 to that shown in Fig. 3 the eyele oitE operation olf the engine as a whole, will be completed.

From the foregoing it will be observed that l have provided a very etlieient eonstruetion o'l engine in whieh the highest pressure ol. the working charge, whieh oeeurs at the instant ol' ignition, is brought. to bear on a moving-piston and not alone on a dead piston at. the time it. passes its dead Center, thus utilizingl the entire expansive :torre ol the, ignited Charge `from the instant o'lI ignition until the pressure o1 the rharge has `fallen to praetieally atmos` plierie pressure. Again my engine` it will be seen, provides an elleetive method o'l utilizing the heat' energy whieh usually is lost through radiation and eondnetion, to warm the ineoming air whieh unites in the low pressure o vlinder Awith the ignited new eliarge aiter the port -l t, and subse pientlv the ports i3, open up.

lt will he notieed that by my eonslruetion and partieularly b v reference to Fig. 3, that. the eoiilwration ol'A the various pistons is sueh that the piston 23, operating in advanee o'l." the piston 1i', delivers its power to the erank shatt under maximum pressure and as the pressure in the eylindels ll. and is redueed. the seeond hi,ffh pressure piston 17 will deliver its power to the erank shalt; as the pressure ot the workingagent in the eylnders 1l. and 12 is still further redueed the port -lrfl and subseiplenllv the ports -fli open up whereby the eonipound piston or low pressure piston A115 whieh is several times luenee to the crank shaft in com'wction with the two high pressure pistons, 17 and Q3, thus making a very eren delivery of the power to the crank shaft through the various dist rihutions of the working agent pressures. ln this manner l am able to dispense with heavy tty wheels, particularly by employing. two'or more units on a single crank shaft in the well known manner.

l wish to mention that the construction herein shown and described is the preferred one, but l do not wish to be limited thereto or to be understood as limiting myself thereto by the specific disclosure and description of the form ofthe engine herein referred `to as many changes can be made in the construction and design of parts without departing from the invention asset forth in` the appended claims.

That I claim is 1. ln a compound internal combustion engine, a high pressure section and a low pressure section, said low pressure section including a cylinder and a piston, said high pressure section including a plurality of cylinders and pistons, `a crank shaft, a connecting rod between said crank shaft and said low pressure piston, a differential connecting rod between said shaft and said high pressure pistons, piston controlled ducts between one of said high pressure cylinders and said 10W pressure cylinder, a common compression and ignition chamber for all of said high pressure cylinders, means for charging said high pressure cylinders with lworking agent, and means permitting the exhausting of said low pressure cylinder. c

Q. In a compound internal combustion engine, a high pressure section and a lo-w pressure section,said low pressure section including a cylinder and a piston, said high pressure section including a plurality of cylinders and pistons, a crank shaft, a connecting rod between said crank shaft and said low pressure piston, a differential connecting rod between said shaft and said high pressure pistons, piston controlled ducts between one of said high pressure cylinders and said low pressure cylinder, a common compression and ignition chamber for all of said high pressure cylinders, means for charging said high pressure cylinders with working agent, and means permitting the exhausting of said low pressure cylinder, and means for admitting a scavenging agent into said cylinders.

3. In an internal combustion engine` a low pressure cylinder and its piston, a high `pressure cylinder and its piston, a crank shaft and connections'between said crank shaft and said pistons,L intercommunieating.

both pistons, ducts in said high pressure cylinder controlled by said high pressure pistonindependent of the working chamber of said high pressure cylinder, certain of said intercommunicating ducts coperating with said high pressure cylinder ducts to form an exhaust passage from said low pressure cylinder to atmosphere, and means for supplying working agent to the working chamber of said high pressure cylinder.

4. ln an internal combustion engine, a low pressure cylinder and its piston, a high pressure cylinder and its piston, a crank shaft and connections between said crank shaft and said pistons, intercon'ununicating ducts between said cylinders controlled by both pistons, ducts in said high pressure cylinder controlled by said high pressure piston independent of the working chamber of said high said pistons' to pass its dead center ih adi vance of the passage of the other piston past its dead center when the new charge has been compressed, a low ,pressure cylinder, and a low pressure piston operating in the same, a connection between the low pressure piston and the crank shaft, port connections between said low pressure cylinder and one of said high pressure cylinders, an air inlet port for said high pressure cylinders controlled by the piston of that cylinder having the air inlet port, said air inlet port adapted to open While said low pressure cylinder is in communication with the adjacent high pressure cylinder and said low pressure piston is still moving on its out stroke to cause air to be drawn into said high pressure cylinders and scavenge the same, and means for subsequently injecting a charge of gas into said high pressure cylinders to mix with the 'scavenging air and form the working charge.

6. In an internal combustion engine, a pair of high pressure` cylinders, a high pressure piston for each cylinder, a common compression and ignition chamber for said cylinders, alcrank shaft, means causing one of said pistons to pass its dead center in advance ofthe passage of the other piston past its dead center when the new charge has been compressed, a low pressure cylinder and piston, a connection between said crank shaftfand said low pressure piston to cause said "low llt pressure piston to pass through its cycle of i operations at a later interval than that of the high pressure pistons, a controlled duct between said low pressure cylinder and the working chamber of one of said high pressure cylinders to admit the partly expanded charge from the high pressure cylinder into said low pressure cylinder to cause all of said pistons to simultaneously operate during a portion of their cycles under the influ-l ence of the ignited charge, means for charging said high pressure cylinders, and an exhaust duct for said low pressure cylinder.

7. In an internal combustion engine, a pair of high pressure cylinders, a high pressure piston for each cylinder, a common compres` sion and ignition chamber for said cylinders, a crank shaft, means causing one of said pistons to pass its deadcenter in advance of the passage of the other piston past its dead center when the new charge has been compressed, a low pressure cylinder and piston,`

a connection between said crankshaft and said low pressure piston to cause said low pressure piston to pass through its cycle of operations at a later interval than that of the high pressure pistons, a controlled duct between said low pressure cylinder and the working chamber of one of said high pressure cylinders to admit the partly expanded charge from the high pressure cylinder into said low pressure cylinder to cause all of said pistons to simultaneously operate during a portion of their cycles under the influence of the ignited charge, means for charging said high pressure cylinders, and an exhaust duct for said low pressure cylinder, controlled by said low pressure piston.

8. In an internal combustion engine, `a pair of high pressure cylinders, a high pressure piston for each cylinder, a common compression and ignition chamber for said cylinders, a crank shaft, means causing one of said pistons to pass its dead center in advance of the passage of the other pis` ton past its dead center when the new charge has been compressed, a low pressure cylinder and piston, a connection between said crank sha-ft and said lowpressure piston to cause said low pressure iston to pass through its cycle of .operations at a later interval than that ofthe high pressure pistons, a controlled duct between said low pressure cylinder and the working chamber of one of said high pressure cylinders to admit the partly expanded charge from thehigh pressure cylinder into said low pressure cylinder to cause all of said pistons to simultaneously operate during a portion of their cycles under the intluence of the ignited charge, means for charging said high pressure cylinders, and an exhaust duct for said low pressure cylinder, controlled by said low pressure piston, and by one of said high pressure pis- I tons.

9. In an internal combustion engine, a pair ofhigh pressure cylinders, a high pressure piston for each cylinder, a common compression and ignition chamber for said cylinders, a crank shaft, means causing one of said pistons to pass its dead center in advance of the passaUe ofthe other piston past its dead center when the new charge has been compressed, a low pressure cylinder and piston, a connection between said crank shaft and said low pressure piston to` cause said low pressure piston to pass through its cycle of operations at a later interval than that of the high pressure istons, a controlled duct between said 0W pressure cylinder and working chamber of one of said high pressure cyllnders to admit the partly expanded charge from the high pressure cylinder into said low pressure cylinder to cause all of said pistons to simultaneously operate during a portion of their cycles under the influence of the ignited charge, means for charging said high pressure cylinders, and an exhaust duct for said low pressure cylinder, one of saidthigh pressure cylinders having a controlled air intake port to coperate with said low pressure piston to pass a scavenging agent into said cylinders when said intercommunicating port is open.

10. In an internal combustion engine, a

pair of high pressure cylinders, a high pressure piston for each cylinder, a common compression and ignition chamber for said cylinders. a crank shaft, means causing one of said pistons to pass its dead'center in advance of the passage ofthe other piston past its dead center when the new charge has been compressed, a low pressure cylinder and piston, a connection between said crank shaft and said low pressure piston to cause said low pressure piston to pass through its cycle of operations at a later interval than that of the high pressure istons, a controlled duct between said ow pressure cylinder and Working chamber of one of said high pressure cylinders to admit the partly expanded charge from the high pressure cylinder into said low pressure cylinder to cause all of said pistons to simultaneously operate during a portion of their cycles under the influence of the ignited charge, means for charging said high pressure cylinders, andan exhaust duct for said low pressure cylinder, one of said high pressure cylinders having a controlled air intake port to cooperate with said low pressure piston to pass a scavenging agent into said cylinders when said intercommunicating port is open, and means for relieving any vacuum that may be formed in said high pressure cylinders.

l1. In an internal combustion engine of sure cylinders and their pistons, a single low pressure cylinder and its piston, acrank shaft, a connecting rod between said low pressure piston and said shaft, a differential connection between said Shaft and said high pressure pistons to cause one of said high pressure pistons to pass its dead center in advance of the other at the commencement of their working strokes, a common compression and ignition chamber for both high pressure cylinders, intercommunicating `ducts between said low pressure cylinder and the working chamber of one of said high pressure cylinders, said ducts being controlled by the said lo-w pressure piston yconnection between said shaft and said high pressure pistons to cause one of said high pressure pistons to pass its dead center in advance of the other at the commencement of their working strokes,fa common coinpression andignition chamber for both high pressure cylinders, interconiniunicating ducts between said low pressure cylinder and the working chamber of one of said.high pressure cylinders, saidv ducts being controlled by said low pressure piston and the high pressure piston in the cylinder with which said ducts communicate, means for charging said high pressure cylinders with fresh working agent, said low pressure piston ,operating during a part of its cycle of movement in co-peration with one of said high pressure pistons for drawing scavenging agent into all ofisaid cylinders, said low pressure piston also operating under another part of its cycle of movement in cooperation with the saine high pressure piston for exhausting the low pressure cylinder contents to atmosphere. k

13. In an internal' combustion engine, a pair of high pressure cylinders and their pisi tons, a single low pressure cylinder and its piston, the first of said high pressure cylinders having a piston controlled air inlet port, a fuel charging pump for injecting fuel into said first high pressure cylinder at intervals, a compression and ignition chamber for said high pressure cylinders, intercoininiiiiicating ducts between the second of `-said high pressure cylinders and/said low ypressure cylinder, said last named ducts being controlled by both the second high pressure pistonV and/thelow pressure piston, said ip'zaeaa second high pressure cylinder having exhaust ports independent and outl yof communication with the working chamber of the saine', said exhaust ports being controlled by said high pressure piston, intercouiinuiiicatng exhaust ducts between said second high pressure cylinder and said low pressure cylinder, and controlled by said low pressure piston and said second high pressure piston, a single crank shaft, means connecting the pistons with said crank shaft to impart motion thereto, substantially as shown and described.

14.-In an internal combustion engine, a pair of high pressure cylinders and their' pistons, a 'single low pressure cylinder and its piston, the. first ofsaid high pressure cylinders having a piston controlled air inlet port, a fucl charging pump for injecting fuel into said first high pressure cylinder' at intervals, a compression andignition chamber for said high pressure cylinders, intercomiiiunicating ducts between the second of said vhigh pressure cylinders and said low pressure cylinder, said last named ducts being controlled byboth the second high pressure piston and the low pressure piston, said second high-pressure cylinder having exhaust ports independent and out of communication with the working chamber, of the saine, said exhaust ports being controlled by said yhigh Vpressilre piston, intercommunicating exhaust ducts between said second high pres'- sure cylinder and saidllow pressure clyinder, and controlled by said low pressure piston and said second highpressure'piston` a. single crank shaft, means connecting the pistons with said crank shaftto impart motion thereto, the connection between said high pressure pistons and the crank shaft including a differential connection whereby one of said high pressure pistons will pass its dead center in advance of the other high pressure piston, substantially as shown and described. i A

15. ln an internal combustion engine, a pair of high pressure cylinders Vand their pistons, a single low pressure cylinder and its piston, the first of said high pressure cylindershaving a piston controlled air inlet port, a fuel charging pump for injecting fuel into said first high pressure cylinder at intervals, a compression and ignition chamber `for said high pressure cylinders, intercommunicating ducts between the second ofsaid high pressure cylinders and said low pressure cylinder, said last' named ducts being 'controlled by botlrnthe second high pressure piston and the low pressure piston` said second high pressure' cylindery having exhaust portsindependent and out of coinmunication with the working chamber of the same, said exhaust ports being controlled byl said high pressure-piston, intercommunicating exhaust ducts between said second high pressure cylinder and said low pressure cylinder, and controlled by said low pressure piston and said second high pressure piston, a single crank shaft, means connecting the pistons with said crank shaft to impart motion thereto, the connection between said high pressure pistons and the crank shaft including a diierential connection whereby one of said high pressure pistons will pass its dead center in advance of the other high pressure piston, said intel-communicating ducts between said low pressure cylinder and the working chamber of the iirst of said high pressure cylinders including a main set of ducts and an auxiliary duct, the auxiliary ducts being arranged to be open in advance of the main ducts.

'16. In an internal combustion engine, a high pressure cylinder, a high pressure piston operating in said cylinder, a low pressure cylinder and a low pressure piston operating in said low pressure cylinder, valveless intercommunicating ducts effecting communication between said two cylinders and controlled by the respective pistons,

means for charging the high pressure cylinder with a new charge while said intercommunicating ducts are closed, connections between said pistons causing one of said pistons to travel in advance ot the other. exhaustports for said high pressure cylinder, said high pressure piston having a passage effecting communication between said exhaust ports and certain of said intercommunicating ports at times to permit the spent charge from said low pressure cylinder to pass into said high pressure cylinder, around said high pressure piston, and through said exhaust ports of said high pressure cylinder to atmosphere.

17. In an internal combustion engine, a pair of high pressure cylinders, a high pressure piston for each cylinder, a common compression and ignition chamber for said cylinders in constant communication with the same, a crank shaft, means causing one of said high pressure pistons to pass its dead center in advance of the passage of the other piston past its dead center when the new charge has been compressed, a low pressure cylinder', a low pressure piston intercommunicating ducts between one of said high pressure cylinders and said low pressure cylinder controlled by the respective high and low pressure pistons, and means for discharging the spent charge from the low pressure cylinder to atmosphere, together with means for charging said high pressure cylinders with new working agent.

18. In an internal combustion engine, a pair of high pressure cylinders, a high pressure piston for each cylinder, a common compression and ignition chamber for said cylinders in constant communication with the same, a crank shaft, means causing one of said high pressure pistons to pass its dead center 1n advance of the passage of the other piston past its dead center when the new charge has been compressed, a low pressure cylinder, a low pressure piston intercommunicating ducts between one of said high pressure cylinders and said low pressure cylinder controlled by the respective high and low pressure pistons, and means for discharging the spent charge from the low pressure cylinder to atmosphere, together with means for charging said high pressure cylinders with new working agent, and means for admitting scavenging air into said high pressure cylinders at other times.

19. ln an internal combustion engine, a pair of high pressure cylinders, a high pressure piston for each cylinder, a common compression and ignition chamber for said cylinders, a crank shaft, a differential connection between said high pressure pistons with said Crank shaft, said'differential connection causing one of said high pressure pistons to pass its dead center in advance of the passage of the other high pressure piston past its dead center, a low pressure cylinder and its piston, a connection between sa-id low pressure piston and said crank shaft. intel-commilnicating ducts between one of said high pressure cylinders and said low pressure cylinder, controlled by the respective high and low pressure pistons, and means controlled b v one of said high pressure pistons for passing the spent mixture to atmosphere under the infiuence of said low pressure piston when working on its exhausting stroke. together with means for admitting new charges of working agent to said high pressure cylinders and for withdrawing the old charges from said high pressure cylinders into said low pressure cylinder.

WILLIAM JAMES WRIGHT. lVitnesses J. S. Bowsnn, FREDERIC 1V. Elm. i 

